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Dong Q.Z.,Shaanxi Fast Auto Drive Group Company | Zhu Z.W.,Beijing Petroleum Machinery Factory
International Heat Treatment and Surface Engineering | Year: 2014

In this paper, the carburising process of steel foil was simulated by numerical method and the carbon transfer coefficient β at the workpiece surface was calculated with the conventional formula for the steel foil carburising test. The results indicated that foil thickness, carburising time and carbon diffusion coefficient in foil apparently affect the calculated carbon transfer coefficient, which always has a smaller value than the preset β value (the true value) and decreases with decreasing carbon diffusion coefficient. This paper suggests that the conventional formula is applicable only when carbon diffusion coefficient in foil is close to infinity; otherwise, the calculated β has obvious error and consequently, gives false information about the influences of other test factors. We propose a new calculation method based on the analytical solution of the diffusion equation during steel foil carburising and a supplementary test, with which the calculated β coefficient is close to the true value, and the carbon diffusion coefficient can be obtained simultaneously. © 2014 IHTSE Partnership. Source

Wang M.,Beijing Forestry University | Tao S.,Beijing Petroleum Machinery Factory | Guo J.,Beijing Forestry University | Hao J.,Beijing University of Chemical Technology | Li Q.,Beijing Forestry University
Acta Crystallographica Section E: Structure Reports Online | Year: 2012

In the title complex, [(C4H9)4N] 2[Mo6O18(C9H9NO 2)]·0.5C4H10O, the arylimido ligand is linked to an Mo atom of the Lindqvist-type polyoxidometalate anion by an Mo ≡ N bond of 1.726 (4) Å. The Mo ≡ N - C angles are 160.7 (5) and 167.6(5)° because of disorder affecting the aryl group, and is typical for the imido monodentate behaviour described in analogous hybrids. Light components of the structure are extensively disordered. The aryl ester group is disordered over two positions with occupancies refined to 0.559 (3) and 0.441 (3). Both independent tetrabutylammonium cations have butyl chains partially split over two sites, with occupancies as in the aryl group of the anion. Finally, the ether solvent molecule is disordered around an inversion centre. In the crystal, cations and anions interact via C - H⋯O contacts, involving O atoms of the polyoxidometalate anion and the ester group of the arylimido ligand as acceptor groups. © 2012 International Union of Crystallography. Source

China National Petroleum Corporation, Cnpc Drilling Research Institute and Beijing Petroleum Machinery Factory | Date: 2013-06-18

An information transmission apparatus for logging while drilling comprises a hollow drilling rod and at least one cable. The drilling rod comprises at least one first drilling rod member and at least one second drilling rod member spliced to each other alternately. The first drilling rod member comprises a through hole, and the second drilling rod member comprises a stepped hole. The cable comprises a fixed end, a connected end, and a folded portion connect the fixed end to the connected end. Each of the cables is fixed in the stepped hole through a fixed end or is connected to a connected end of an adjacent cable. The connected end may be stretched along the stepped hole, and stretched through the through hole to be electrically connected to a logging instrument or a fixed end of the adjacent cable. The apparatus provides protection for a cable through a hollow drilling rod, thereby improving the transmission reliability.

Li J.-L.,Beijing Institute of Technology | Zhao Y.,Beijing Institute of Technology | Zhao Y.,China Academy of Aerospace Systems Science and Engineering | Li M.-H.,Beijing Petroleum Machinery Factory
Beijing Ligong Daxue Xuebao/Transaction of Beijing Institute of Technology | Year: 2013

Flexibility is a key attribute of engineering systems to cope with effects of uncertainty. Flexibility of engineering systems has become a hot area of abroad multidisciplinary studies recently. In this paper, the concept, identification and measurement, and evaluation of engineering systems flexibility are reviewed. Based on analyzing the limitation of the current studies, some research opportunities in the area of engineering systems flexibility are proposed. Source

Li N.,China National Offshore Oil Corporation | Tian J.,China National Offshore Oil Corporation | Zheng Q.,China National Offshore Oil Corporation | Ren Z.,Beijing Petroleum Machinery Factory
Well Testing | Year: 2015

Through the introduction of judging indexes of gas storage rate, miscible volume and miscible effect, using the method combined with the actual dynamic and numerical simulation, applying multiple linear regression algorithm, a multi-factor screening (sequence) method has been built, the evaluation method of CO2 miscible flooding is improved, and the main control factors affecting development effect are obtained which provides a reference for planning the development of CO2 flooding. The results show that the gas storage rate, miscible volume and miscible effect can effectively evaluate the development effect of miscible; degree of heterogeneity has most obviously influence on oil recovery degree; secondly is the injective fluid; lastly is the original formation pressure; the injective fluid has most obviously influence on miscible effect effects; secondly is the original formation pressure, lastly is the reservoir heterogeneity. ©, 2015, Well Testing. All right reserved. Source

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